JPH1114264A - Rotary kiln - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a large-sized rotary kiln having a furnace core duct with a large inlet diameter not found heretofore and with a long axis. SOLUTION: This indirect heating type rotary kiln is constructed such that at least both ends of a metallic furnace core duct 2 are rotatably supported by rollers through tires externally fitted to them and a combustion chamber is formed at an outer circumference of the furnace core duct between the tires, wherein a tire 5 is externally fitted to an intermediate section of the furnace core duct 2 through many blocks 20 and some removable spacers 21 and then the tire 5 is rotatably supported by the rollers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to
The present invention relates to an indirect heating type rotary kiln used for firing, oxidation treatment of metal powder, reduction treatment of metal raw materials, treatment of earth and sand containing organic substances, and the like.

[0002]

2. Description of the Related Art Conventionally, as this type of indirectly heated rotary kiln 40, as shown in FIGS. 11 and 12, both ends 42 and 43 of a metal furnace core tube 41 are fitted around a metal core tube 41. It is rotatably supported via a pair of rollers 46, 46 via tire-made tires 44, 45, respectively, and a combustion chamber 47 is formed on the outer periphery of the furnace core tube 41 between the tires 44, 45. Oil is burned into the combustion chamber 4 by the burner 48.
The material burned in the furnace 7 and supplied into the furnace core tube 41 is processed.

Incidentally, 49 is an exhaust pipe, 50 is an exhaust collecting pipe,
51 is an exhaust blower. As a method of attaching the tires 44 and 45 to the furnace core tube 41, as shown in FIGS. 13 and 14, a method of directly welding the ring-shaped tire 44 to the furnace core tube 41, and FIGS. So, the furnace tube 4
A method in which a number of getters 52 are welded on one outer circumference and a tire 44 is welded on the getters 52. Further, as shown in FIG. After the fitting, a method is employed in which slip stoppers 53 are welded to both sides of each getter 52 and the tire 44 in the axial direction.

When the rotary kiln 40 is used in a high temperature range of 800 ° C. or higher, the total length of the kiln is determined within the allowable range of the hot deflection of the furnace core tube 41 between the fulcrums. There was a limit.

[0005]

By the way, in order to obtain a rotary kiln having a large-diameter and long-axis furnace core tube used in a high-temperature region of 800 ° C. or higher, that is, a large-diameter furnace tube, a furnace core tube is required. It is necessary to support the entire furnace core tube at three or more points in order to keep the hot deflection between the fulcrums within an allowable range.

[0006] When the furnace core tube is supported at three points, the intermediate supporting portion of the furnace core tube has a higher temperature range than the supporting portions provided at both ends of the furnace core tube, so that the tire is rotatably supported. It is indispensable to take measures to prevent the heat of rollers and roller bearings
Further, there is a problem that the tire provided at the intermediate support portion needs to have a structure that can be easily replaced without removing tires at both ends of the furnace core tube.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and has as its object to provide a large-diameter non-conventional tire having a structure for preventing heat in an intermediate support portion and having a structure that allows easy tire replacement. Another object of the present invention is to provide a large indirect rotary kiln employing a long core furnace tube.

[0008]

According to the present invention, the following technical measures have been taken in order to achieve the above object. That is, according to the present invention, at least both ends of the metal furnace tube are rotatably supported by rollers via metal tires fitted to the outside thereof, and a combustion chamber is formed around the furnace tube between the tires. A rotary kiln of an indirect heating type, wherein a tire is externally fitted to an intermediate portion of the furnace core via a getter and a detachable spacer, and the tire is rotatably supported by rollers. I have.

In this case, a sufficient distance can be ensured by the presence of the spacer between the furnace core tube in the high temperature region at the intermediate support portion and the roller supporting the core tube.
Radiation heat from the furnace core tube received by the rollers and roller bearings is reduced, and the heat effect is reduced. It should be noted that the diameter between the getter and the spacer and between the spacer and the tire are each 2 mm in diameter.
By providing a gap of about 7 mm, conductive heat received by the roller can be reduced.

Further, according to the present invention, since the spacer is divided in the circumferential direction or the axial direction, or in the circumferential direction and the axial direction, it is easy to assemble and disassemble, and to easily replace the tire. -Since the spacer and the tire are independent components, when producing each component, a material can be selected in consideration of heat resistance, mechanical strength, abrasion resistance, and the like.

Further, according to the present invention, since the inner diameter of the tire at the intermediate portion is made larger than the outer diameter of the tire at both ends of the furnace core tube, the spacer is removed when the tire at the intermediate support portion is replaced. Accordingly, the tire at the intermediate portion can pass over the tire at both ends of the furnace core tube, and therefore, the tire at the intermediate portion can be easily replaced without removing the tire at the end portion.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of a three-point support type rotary kiln 1 of an indirect heating type according to the present invention. The rotary kiln 1 includes a metal shaft 2 made of a long-axis metal, and metal tires 3, 4, 4 which are exchangeably fitted to both ends 2 A, 2 B and an intermediate portion 2 C of the furnace core 2.
5, a gantry 6, and the tire 3
Roller bearing tables 8, 9, 1 each having two rollers 7A, 7B rotatably supporting the furnace core tube 2 through.
0, the combustion chamber casings 11 and 12 surrounding the outer periphery of the furnace core tube 2 between the tires 3 to 5, and the exhaust pipes 13 and 14 and the exhaust collecting pipe 15 connected to the upper portions of the casings 11 and 12.
16, a burner 17, 18 and an exhaust blower 19.

The mounting structure of the tires 3 and 4 provided at both ends 2A and 2B of the furnace core tube 2 is shown in FIGS.
7 can be adopted. And
The tire 5 supporting the intermediate portion 2C of the furnace core tube 2 is shown in FIGS.
As shown in FIG. 5, a ring-shaped spacer 2 is attached to a getter 20 welded to the outer periphery of the intermediate portion 2C at regular intervals in the circumferential direction.
1 is detachably fitted to the outside. The inner diameter of the tire 5 is larger than the outer diameter of the tires 3 and 4 so that the tires 5 can ride over the tires 3 and 4 at both ends 2A and 2B.

A spacer displacement preventing guide 22 is welded to each of the getters 20 on both sides of the spacer 21 in the axial direction of the furnace core tube 2. The spacer 21
Flange portions 2 for tire positioning on both outer circumferences in the axial direction
Six pieces 21A, 21B, 21 are obtained by dividing the ring having 3 and 23 into three parts in the circumferential direction and two parts in the axial direction.
C and a plurality of sets of connecting bolts 24 and nuts 25 for connecting the pieces 21A to 21C in the axial direction, respectively, so as to be disassembled. The pieces 21A to 21C of the spacer 21 are, as shown in FIG.
Each has a different size, and the split angle is 180 for piece 21A.
The angle of the piece 21B is 120 degrees, and the angle of the piece 21C is 60 degrees, so that assembly and disassembly can be performed easily and efficiently.

The distance between the getter 20 and the spacer 21 and between the spacer 21 and the tire 5 is 2 to 7 mm in diameter.
Gap S is provided.
Therefore, the heat transfer to the tire 5 via the getter 20 and the spacer 21 can be reduced. Further, both end faces in the axial direction of the tire 5 and the flange portion 2 of the spacer 21 are formed.
3, a gap S1 of about 0.5 to 1.0 mm is provided, and heat transfer to the tire 5 can be reduced by the gap S1.

According to the above embodiment, the spacer 2
1, the distance between the furnace core tube 2 and the rollers 7A and 7B in the high-temperature region (intermediate portion) becomes longer by at least the radial dimension (thickness) of the spacer 21 and becomes longer. Radiant heat applied to the rollers 7A and 7B from above is reduced, and the heat-insulating effect can be enhanced. In addition, each getter 2
The spacer 0, the spacer 21 and the tire 5 are independent components, and therefore, in the manufacture thereof, a material can be selected in consideration of heat resistance, mechanical strength, and abrasion resistance.

In addition, since the inner diameter of the tire 5 provided in the intermediate portion 2C is larger than the outer diameters of the tires 3 and 4 at both ends 2A and 2B, the spacer 21 is connected when the tire 5 is replaced. It can be easily removed by removing the bolt 24 and disassembling it.
Can be pulled out of the furnace core tube 2 by passing over the tire 3 or 4 at the end. When a new tire 5 to be replaced is mounted, the new tire 5 is fitted over the end of the furnace core tube 2, and the tire 3 or 4 at the end is passed over and placed on the getter 20. 2
By inserting 1A to 21C between the tire 5 and each of the getters 20 and connecting them with the connecting bolts 24 and nuts 25, it is possible to easily replace them.

Therefore, the tire 3 or 4 at the end of the furnace core tube 2 can be replaced efficiently without removing it. As described above, according to the first embodiment of the present invention, by supporting the furnace core tube 2 at three points, the hot deflection of the furnace core tube 2 between the fulcrums (tires 3 to 5) can be reduced within an allowable range. A large-sized indirectly heated rotary kiln having a large-diameter, long-axis furnace core tube, which has never existed before, can be provided.
In addition, as described above, the replacement of the intermediate tire is facilitated in addition to the heat insulation measures, and a large-scale rotary kiln can be implemented.

When the spacer 21 is divided into three pieces 21A, 21B, and 21C of large, medium, and small sizes in the circumferential direction as described above, when disassembling, the spacers 21 are sequentially removed from the small pieces 21C, and when assembled, the large pieces 21A are used.
By disassembling and easily disassembling and
Assembly work can be performed. FIG. 6 shows a main part of the second embodiment of the present invention. The difference from the first embodiment is that the spacer 21 is also divided into three parts in the axial direction so that the flange part 23 is independent. The second embodiment has substantially the same operation and effect as the first embodiment. In addition, on the opposing contact surfaces of each of the divided pieces 21A to 21C and each of the flange portions 23,
Steps 26 and 27 in the radial direction are provided, respectively, and the spacer 2
1 can be assembled accurately and easily.

The spacer 21 may be an integral body without being divided as in the case of 21A to 21C. FIG.
Shows a main part of the third embodiment of the present invention. The difference from the second embodiment is that the spacer 21
1A to 21C are provided with flange portions 23, 23 protruding to the inner diameter side and the outer diameter side, the getter 20 is located between the inner diameter side opposing surfaces of the flange portions 23, the guide for slip prevention is omitted, This is because the flange portion 23 has a guide function for preventing slippage, and assembling and disassembling operations are slightly easier than in the first and second embodiments. Further, the welding work of the guide for preventing slippage is unnecessary.

In the third embodiment, the spacer 21
An annular groove 28 for fitting and positioning the spacer divided pieces 21A to 21C is provided on the facing surfaces of the flange portions 23, 23 constituting the above. In addition, the spacer 21
They may be integrated without being divided as in A to 21C.

FIG. 8 shows a modification of the third embodiment, which is different from that shown in FIG. 7 only in that the annular groove on the surface of the spacer 21 facing the flange 23 is omitted.
FIG. 9 shows a main part of the fourth embodiment of the present invention, which is different from the second embodiment in that a detachable second spacer 29 is interposed between the spacer 21 and the tire 5. That is, the second spacer 29 is
The divided pieces 29A to 29 divided into three in the circumferential direction in the same manner as described above.
C is divided into three in the axial direction, and the flange portion 30 for tire positioning is independent, and the divided pieces 29A to 29C are connected in the axial direction by connecting bolts 31 and nuts 32.

The two flange portions 30 in the axial direction of the second spacer 29 protrude toward the outer peripheral side, but do not interfere with the inner peripheral side of the flange portion 23 of the first spacer 21 and come into contact with the outer peripheral surface of the flange portion 23. The inner diameter is made large so that a gap S is formed between them. The gaps S and S1 are provided between the first and second spacers 21 and 29 with respect to the getter 20 and the tire 5 as well as between each other.

According to the fourth embodiment, the assembling / disassembling operation requires a little more time, but the distance between the tire 5 and the outer peripheral surface of the furnace core tube 2 is further increased, and the furnace core tube 2 and the roller 7A in the high temperature region are increased. , 7B, the tire 5
Can be further increased, so that radiant heat from the furnace core tube 2 can be further reduced. The spacer 21 may be an integral body without being divided as in 21A to 21C.

FIG. 10 shows a main part of a fifth embodiment of the present invention.
The flange portions 23 of the divided pieces 21A to 21C are also provided on the inner peripheral side so that each getter 20 has a width that can be fitted between the flange portions 23 and the intermediate portion 2C of the furnace core tube 2.
Is that the guide 22 for preventing slippage is welded to the reinforcing sleeve 33 welded to the core 33, the strength of the intermediate portion 2C of the furnace core tube 2 is increased, and the gap between the rollers 7A, 7B and the furnace core tube 2 is increased. Distance can be more sufficiently secured. In the fifth embodiment, the getter 20 is an integral member in the circumferential direction, and a gap S is provided between the getter 20 and the sleeve 33.

The present invention is not limited to the above embodiment. For example, in the first to fourth embodiments, the reinforcing sleeve can be welded and run around the intermediate portion 2C of the furnace core tube 2, and furthermore, In addition, the number of supporting portions of the furnace core tube 2 is set to three or more, and a large-diameter long-axis rotary kiln can be configured.

[0027]

According to the present invention, as described above, the tire is externally fitted to the intermediate portion of the furnace core tube via the getter and the detachable spacer, and the tire is rotatably supported by the rollers. Therefore, the furnace core tube can be supported at three or more points, and the distance between each fulcrum is set within the allowable range of the hot deflection of the furnace core tube. A large indirect rotary kiln can be manufactured, and the processing capacity can be increased.

Further, by assembling the spacer in a divided structure, assembly and disassembly are easy. And since the inner diameter of the middle tire is larger than the outer diameter of the tire at both ends of the furnace core tube, after disassembling and removing the spacer, remove the middle tire by riding over the tire at one end. Therefore, the tire at the end does not need to be removed, and the tire replacement operation can be performed easily and efficiently.

[Brief description of the drawings]

FIG. 1 is an overall front view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

3 is an enlarged view of a main part of FIG. 2 (cross section taken along line BB in FIG. 4).

FIG. 4 is a sectional view taken along line CC of FIG. 3;

FIG. 5 is an enlarged view of a part D in FIG. 4;

FIG. 6 is a sectional view showing a main part of the second embodiment of the present invention (FIG. 4);
FIG.

FIG. 7 is a sectional view (FIG. 4) showing a main part of the third embodiment of the present invention.
FIG.

FIG. 8 is a sectional view showing a modification of the third embodiment.

FIG. 9 is a sectional view (FIG. 4) showing a main part of a fourth embodiment of the present invention;
FIG.

FIG. 10 is a cross-sectional view (a cross-sectional view corresponding to a portion D in FIG. 4) illustrating a main part of a fifth embodiment of the present invention.

FIG. 11 is a front view showing a conventional example.

FIG. 12 is a left side view of FIG. 11;

FIG. 13 is an enlarged cross-sectional view taken along line EE of FIG. 11;

FIG. 14 is a sectional view taken along line FF of FIG. 13;

15 is a cross-sectional view (a cross-section corresponding to line EE in FIG. 11) showing another conventional example.

16 is a sectional view taken along line GG of FIG.

FIG. 17 is a cross-sectional view showing still another conventional example (G-
FIG.

[Description of Signs] 1 Rotary kiln 2 Furnace core tubes 2A, 2B Both end portions 2C Intermediate portion 3 Tire 4 Tire 5 Intermediate portion tire 7A, 7B Roller 11, 12 Combustion chamber casing 20 Getter 21 Spacer 21A, 21B, 21C Split piece 23 Flange part 29 Second spacer 29A, 29B, 29C Divided piece 30 Flange part

Continued on the front page (72) Inventor Toshiyuki Hanatani 1-1-1 Nakamiya Oike, Hirakata-shi, Osaka Inside Kubota Hirakata Factory

Claims (4)

[Claims] At least both ends of a metal furnace core tube are rotatably supported by rollers via metal tires externally fitted to the metal furnace core tube, and a combustion chamber is formed around the furnace core tube between the tires. A rotary kiln of an indirect heating type, wherein a tire is externally fitted to an intermediate portion of the furnace core tube via a getter and a detachable spacer, and the tire is rotatably supported by rollers. Rotary kiln. 2. The rotary kiln according to claim 1, wherein the spacer is divided in a circumferential direction. 3. The rotary kiln according to claim 1, wherein the spacer is divided in an axial direction. 4. The rotary kiln according to claim 1, wherein the inner diameter of the tire at the intermediate portion is larger than the outer diameter of the tire at both ends of the furnace core tube.